Field of the Invention
The present invention relates to wireless communications, and more particularly, to a method of allocating a radio resource in a wireless communication system and an apparatus using the method.
Related Art
To overcome a restriction of a service area and a limitation of a user capacity, the wireless communication system provides a communication service by dividing the service area into a plurality of cells. This is referred to as a multi-cell environment.
Types and features of service traffic and application programs that can be used in the wireless communication system have been diversified. Accordingly, a wireless data usage pattern of a user equipment (UE) has also been diversified. For example, a UE which uses a large amount of data and a UE which uses a small amount of data may exist at the same time in the same network. In addition, the same UE may have a different data pattern in use according to a place, a current speed, etc. If a data usage pattern differs from one UE to another, the wireless communication system may preferably provide a service suitable for a data usage pattern of each UE. In doing so, an effective network management is possible, and a service suitable for a requirement of a UE can be provided from a perspective of the UE.
Meanwhile, in order for the wireless communication system to effectively use a limited frequency, time resource and to decrease a network interference, techniques for allocating a wireless resource have been proposed, such as frequency reuse, carrier aggregation (CA), inter-cell interference coordination (ICIC), etc.
The frequency reuse is for adjusting a bandwidth by dividing an available frequency band by a frequency reuse factor K so that neighboring cells use different frequency bands. The CA is for aggregating and using necessary carriers by dividing a system band into a plurality of carriers. The ICIC is for dividing and using a radio resource in a frequency or time axis through cooperation between neighboring cells to decrease interference between base stations (BSs) of a network.
As such, many techniques related to radio resource allocation have been proposed, but a method of allocating a radio resource by considering a data amount required by UEs in a network has not been proposed yet. If the radio resource is allocated without consideration of the data amount required by the UEs, a quality of experience (QoE) of the UE may not be satisfied, or the radio resource is wasted, thereby causing deterioration in system performance.
For example, in long term evolution (LTE) release (Rel)-10, a BS controls interference between BSs by applying a time-domain ICIC technique. When the BS transmits a frame including a plurality of subframes to the UE, not all subframes contain data, but a special subframe called an almost blank subframe (ABS) is used. A physical downlink shared channel (PDSCH) is not used for a specific time.
However, although interference can be decreased by giving more weight to the ABS, the QoE of the UE cannot be satisfied since a throughput of the BS is decreased. Without the ABS, that is, without applying the ICIC technique, a QoE of a cell-edge UE is significantly decreased due to interference between BSs.
As such, since the conventional technique determines a radio resource to be allocated without consideration of a data amount required by UEs in a network, the radio resource is used ineffectively.